Vibrating surgical instruments for blunt dissection and methods for use thereof

ABSTRACT

A dissector including a body, a first arm, a second arm, and a string and methods for use thereof. The first arm extending from the body towards a distal end thereof and the second arm extending from the body towards a distal end thereof. One end of the string is coupled to the first arm adjacent the distal end thereof and the other end of the string is coupled to the second arm adjacent the distal end thereof. The first and second arms have an expanded configuration such that the string is taut and have a collapsed configuration such that the string is slack. The string is configured to dissect tissue when the first and second arms are in the expanded configuration. The string may oscillate to dissect tissue. The distal ends of the first and second arms may atraumatically dissect tissue.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims the benefit of and priority to U.S. ProvisionalPatent Application No. 61/980,645, filed Apr. 17, 2014, the entiredisclosure of which is incorporated by reference herein.

BACKGROUND

1. Technical Field

The present disclosure relates to surgical instruments and, morespecifically, to vibrating surgical instruments for blunt dissection oftissue and methods for use thereof.

2. Discussion of Related Art

In many types of surgery, it is necessary to remove or displace tissuein order to perform a procedure. Often, this is to improve a surgeon'svision in an area of interest where more delicate operations need to beperformed or may be to remove tissue which is in the way for a procedureas it prevents the surgeon from accessing the area of interest with thetools they need to operate on it. One of the more common types ofsurgery where removal of tissue is necessary is on surgery related tothe bowels where it is often necessary to remove tissue in the form ofadhesions to access the bowels.

Depending on the nature of the tissue to be removed and its location,various different types of tools are desirable. The most common type ofsurgical tool to remove tissue is undoubtedly a sharp device such as ascalpel, blade, saw, or drill. These types of devices are necessary forvirtually any type of surgery to be performed as they allow the surgeonto cut through what would otherwise be a seamless body structure. Inmany situations, however, they are preferably not used as should thecutting instrument slip slightly, a dangerous situation could occur.When a surgeon is working near essential blood vessels, organs, or othersensitive structures, misplacement or deviation of a sharp device canresult in potential injury.

One way to avoid this type of injury is to utilize a tool that issuitable for separating two types of matter along an existing seam orconnection, but is generally unsuitable for “cutting” into seamlessmatter. This is often referred to as a blunt dissection instrument.Blunt dissection generally allows tissues to be dissected atraumaticallyby simply separating the tissue along existing seams or natural planes.That is, the tool separates along natural separations, conjunctions, orfaults, without the tool creating a new seam. This type of instrumentfacilitates in surgical exposure and tissue retraction both because ofreducing danger to neighboring tissue and reducing trauma from manmadeseparation.

While blunt dissection is a useful medical procedure, the tools forblunt dissection are often ill suited for the task. Current tools maynot provide sufficient force to separate structures without an existingseam and are generally incapable of generating a new seam or separationon its own.

SUMMARY

In an aspect of the present disclosure, a dissector includes a body, afirst arm, a second arm, and a string. The first arm extends from thebody to a first distal end and the second arm extends from the body to asecond distal end. One end of the string is coupled to the first armadjacent the first distal end and the other end of the string is coupledto the second arm adjacent the second distal end. The string is tautwhen the first and second arms are in the expanded configuration and thestring is slack when the first and second arms are in a collapsedconfiguration. The string is configured to dissect tissue when the firstand second arms are in the expanded configuration.

In embodiments, the first and second distal ends are configured toatraumatically dissect tissue. The first and second arms may be biasedtowards the expanded configuration.

In some embodiments, the dissector includes a tube that defines a lumen.The body of the dissector may be slidably disposed within the lumen suchthat the first and second arms extend from a distal end of the tube inthe expanded configuration and are at least partially disposed withinthe lumen in the collapsed configuration. The tube may engage the firstand second arms to transition the first and second arms from theexpanded configuration to the collapsed configuration. In the collapsedconfiguration, the first and second distal ends protrude from a distalend of the tube to atraumatically dissect tissue. The first and secondarms may have a transport configuration such that the first and seconddistal ends are disposed within the lumen proximal to a distal end ofthe tube.

In certain embodiments, in the collapsed configuration the first andsecond distal ends may protrude from a distal end of the body toatraumatically dissect tissue. The first and second arms may have atransport configuration such that the first and second distal ends aredisposed within the body proximal to a distal end of the body.

In particular embodiments, the first and second arms are coupledtogether and to the body by a pivot pin. The body may define a slotdefined in sidewalls of the body parallel to a longitudinal axis of thebody. The pivot pin may be slidably disposed within the slot. Thedissector may include a biasing member disposed about the pivot pintthat biases the first and second arms towards the expandedconfiguration. The biasing member may be a torsion spring. In certainembodiments, the dissector includes a retraction member coupled to thepivot pin. The retraction member may be configured to retract the pivotpin towards a proximal end of the slot.

In embodiments, the dissector includes a vibration mechanism that isconfigured to oscillate the string traverse to or along a longitudinalaxis of the body. The dissector may include first and second jaw memberscoupled together at a pivot pin. The first distal end of the first armmay be disposed within the first jaw member and the second distal end ofthe second arm may be disposed within the second jaw member. The distalends of the first and second jaw members may be configured toatraumatically dissect tissue. The first and second jaw member may beconfigured to limit tissue contacting the string when the first andsecond arms are in the expanded configuration. Proximal portions of thefirst and second arms may extend proximally within the body. A vibrationmechanism may be disposed within the first jaw member.

In some embodiments, the vibration mechanism includes a magnetic coiland a magnet. The magnet may be disposed on the first arm adjacent thefirst distal end and the magnetic coil may be positioned adjacent themagnet. The magnetic coil is configured to alternately attract and repelthe magnet as energy is applied to the magnetic coil such that thestring is oscillated.

In certain embodiments, the vibration mechanism includes a rotaryelement and an eccentric mass. The rotary element is disposed on thefirst arm adjacent the first distal end. The eccentric mass is rotatableby the rotary element to induce oscillation of the string.

In particular embodiments, the vibration mechanism includes apiezoelectric actuator associated with the first arm that inducesoscillation of the string when energy is applied to the piezoelectricactuator. The piezoelectric actuator may be a stripe actuator disposedalong the first arm substantially parallel to a longitudinal axis of thefirst arm or may be a stack actuator disposed adjacent the first distalend.

In other aspects of this disclosure, a dissector includes a bodydefining a longitudinal axis, a first shaft extending from the body, apeanut, and a vibration mechanism. The peanut is disposed over andcoupled to a distal end of the first shaft and configured toatraumatically dissect tissue. The vibration mechanism is configured tooscillate the peanut in a transverse direction to the longitudinal axisof the body or an axial direction to the longitudinal axis of the body.

In embodiments, the dissector includes a second shaft and a knife. Thesecond shaft is slidably disposed within the first shaft and has aretracted position such that a distal end of the second shaft isadjacent the distal end of the first shaft. The knife is coupled to thedistal end of the second shaft and is disposed entirely within thepeanut when the second shaft is in the retracted position. The knife isconfigured for sharp dissection of tissue in contact therewith. Thesecond shaft may have a first exposed position such that the distal endof the second shaft extends from the distal end of the first shaft andthe knife is at least partially exposed from a distal end of the peanut.The second shaft may have a second exposed position such that the distalend of the second shaft extends from the distal end of the peanut andthe knife is fully exposed from the distal end of the peanut. The firstshaft may engage the second shaft such that the vibration mechanismoscillates the knife.

In yet another aspect of the present disclosure, a method for dissectingtissue includes inserting a dissector within a surgical site in acollapsed configuration, dissecting tissue with first and second distalends, expanding first and second arms of the dissector from a collapsedconfiguration to an expanded configuration, and dissecting tissue withthe string. In the collapsed configuration the string is slack and inthe expanded configuration the string is taut. The dissector may be anyof the dissectors disclosed herein including a body, a first arm, asecond arm, and a string.

In aspects, dissecting tissue with the first and second distal endsincludes oscillating at least one of the first and second arms with avibration mechanism. Dissecting tissue with the string may includeoscillating the string with a vibration mechanism.

In some aspects, the method may include collapsing the first and secondarms to the collapsed configuration after dissecting tissue. The methodmay include dissecting tissue with the first and second distal ends ofthe dissector after collapsing the first and second arms. Collapsing thefirst and second arms may include retracting a pivot pin within a slotdefined in the body to retract portions of the first and second armsinto the body.

In certain aspects, expanding the first and second arms includesretraction a tube from over a distal end of the body with the body isdisposed within a lumen of the tube. Alternatively, expanding the firstand second arms may include extending the body from a distal end of thetube with the body disposed within a lumen of the tube.

In still yet another aspect of the present disclosure, a method fordissecting tissue includes inserting a dissector within a surgical sitein a collapsed configuration, dissecting tissue with distal ends offirst and second jaw members, opening the first and second jaw members,and dissecting tissue with the string. Opening the first and second jawmembers expands first and second arms of the dissector from thecollapsed configuration to an expanded configuration. In the collapsedconfiguration a string coupled to the first and second arms is slack andin the expanded configuration the string is taut between the first andsecond arms. The dissector may be any of the dissectors disclosed hereinincluding a body, a first arm, a second arm, a string, a first jawmember, and a second jaw member.

In aspects, dissecting tissue with the string includes oscillating thestring with a vibration mechanism. In embodiments, oscillating thestring may include energizing a magnetic coil disposed within the firstjaw member adjacent a magnet disposed on the first arm adjacent thefirst distal end. In some embodiments, oscillating the string includesenergizing a rotary element disposed on the first arm adjacent the firstdistal end and within the first jaw member. The rotary element rotatingan unbalanced mass to induce oscillation in the string. In certainembodiments, oscillating the string includes energizing a piezoelectricactuator associated with the first arm. The method may includedissecting tissue with distal ends of the first and second jaw membersafter closing the first and second jaw members

In particular aspects, the method includes guiding tissue to bedissected with the string towards the string positioned between thefirst and second jaw members. The first and second jaw members may guidethe tissue.

In some aspects, the method includes closing the first and second jawmembers collapses the first and second arms to the collapsedconfiguration after dissecting tissue with the string.

In still another aspect of the present disclosure, a method fordissecting tissue includes inserting a dissector within a surgical siteand dissecting tissue with a peanut by oscillating the peanut with avibration mechanism. The dissector may be any of the dissectorsdisclosed herein including a body, a first shaft, a peanut, and avibration mechanism.

In aspects, the method includes extending a knife from within the peanutand dissecting tissue with the knife. The method may include retractingthe knife within the peanut after dissecting tissue.

Further, to the extent consistent, any of the aspects described hereinmay be used in conjunction with any or all of the other aspectsdescribed herein.

BRIEF DESCRIPTION OF THE DRAWINGS

Various aspects of the present disclosure are described hereinbelow withreference to the drawings, wherein:

FIG. 1 is a top view of a dissector provided in accordance with thepresent disclosure in an expanded configuration;

FIG. 2 is a top view of the dissector of FIG. 1 in a collapsedconfiguration;

FIG. 3 is a top view of the dissector of FIG. 1 in a transportconfiguration;

FIG. 4 is a top view of another dissector provided in accordance withthe present disclosure in an expanded configuration;

FIG. 5 is a top view of the dissector of FIG. 4 in a collapsedconfiguration;

FIG. 6 is a top view of the dissector of FIG. 4 in a transportconfiguration;

FIG. 7 is a side view of the dissector of FIG. 4;

FIG. 8 is a side cut-away view of yet another dissector provided inaccordance with the present disclosure with a jaw members in an opencondition and the dissector in an expanded configuration;

FIG. 9 is a side cut-away view of the dissector of FIG. 8 with the jawmembers in a closed condition and the dissector in a collapsedconfiguration;

FIG. 10 is an enlarged side cut-away view of a vibration mechanismdisposed within the jaw members of the dissector of FIG. 8;

FIG. 11 is an enlarged side cut-away view of a another vibrationmechanism disposed within the jaw members of the dissector of FIG. 8 inaccordance with the present disclosure;

FIG. 12 is an enlarged side cut-away view of a yet another vibrationmechanism disposed within the jaw members of the dissector of FIG. 8 inaccordance with the present disclosure;

FIG. 13 is a side view of still yet another dissector provided inaccordance with the present disclosure with a retractable knife in aretracted position;

FIG. 14 is a side view of the dissector of FIG. 12 with the retractableknife in a first exposed position and

FIG. 15 is a side view of the dissector of FIG. 12 with the retractableknife in a second exposed position.

DETAILED DESCRIPTION

Embodiments of the present disclosure are now described in detail withreference to the drawings in which like reference numerals designateidentical or corresponding elements in each of the several views. Asused herein, the term “clinician” refers to a doctor, a nurse, or anyother care provider and may include support personnel. Throughout thisdescription, the term “proximal” refers to the portion of the device orcomponent thereof that is closest to the clinician and the term “distal”refers to the portion of the device or component thereof that isfarthest from the clinician.

Blunt dissection of tissue is preferred when dissecting tissue nearblood vessels or organs that may be damaged when contacted with a sharpinstrument. However, some adhesions between bodily structures may not beeasily dissected when contacted with a blunt dissector. Additionalenergy or movement of the dissector may be required to dissect theseadhesions. By incorporating features in a dissector that permit adissector to bluntly dissect tissue and apply additional energy ormovement to tissue when required to dissect the tissue may reduce thetime of a procedure and thus the cost of the procedure. In addition,such a dissector may increase the safety of a procedure. The additionalenergy or movement may be vibratory movement as detailed below.Additionally or alternatively, a dissector that may bluntly dissecttissue, transition to sharply dissect tissue when needed, and thentransition back to bluntly dissect additional tissue may have the sameadvantages detailed above.

Referring now to FIG. 1, a dissector 10 is provided in accordance withthe present disclosure and includes a body 12, a first arm 14, a secondarm 16, and a string 18. The first arm 14 extends from the body 12 to adistal end 15 and the second arm 16 extends from the body 12 to a distalend 17 in substantially the same direction as the first arm 14. Thedistal ends 15, 17 may be substantially the same distance from the body12. The distal ends 15, 17 are blunt such that the distal ends 15, 17may atraumatically dissect tissue. One end of the string 18 is coupledto the first arm 14 adjacent the distal end 15 and the other end of thestring 18 is coupled to the second arm 16 adjacent the distal end 17.The distal end 15 of the first arm 14 is biased away from the distal end17 of the second arm 17 such that the string 18 is taut. The body 12 ofthe dissector 10 may extend from a lumen of a tube 11.

With additional reference to FIG. 2, the dissector 10 has an expandedconfiguration (FIG. 1) and a collapsed configuration (FIG. 2). In theexpanded configuration, the first and second arms 14, 16 are positioneddistally of a distal end of the tube 11 such that the string 18 is madetaut by the distal ends 15, 17 being biased away from one another. Inthe collapsed configuration, the body 12 is retracted into tube 11 orthe tube 11 is extended over the body 12 such that the tube 11 engagesthe first and second arms 14, 16 to urge the first and second arms 14,16 and the distal ends 15, 17 towards one another and into the collapsedconfiguration. In the collapsed configuration the distal ends 15, 17protrude beyond the distal end of the tube 11 such that the distal ends15, 17 may be used for blunt dissection of tissue. When the in thecollapsed configuration, the string 18 is slack between the first andsecond arms 14, 16.

Referring to FIG. 3, the dissector 10 may include a transportconfiguration such that the distal ends 15, 17 are disposed within thetube 11. In the transport configuration, the string 18 may be disposedwithin the tube 11 or outside of the tube 11. In certain embodiments,the tube 11 may be a catheter tube positioned adjacent to tissue to bedissected and the dissector 10 is delivered through the catheter tube tothe tissue to be dissected.

In embodiments, the dissector 10 includes a vibration mechanism 20configured to laterally vibrate the string 18. The vibration mechanism20 may be operatively associated with one or more of the tube 11, thebody 12, the first arm 14, and the second arm 16.

In use, the dissector 10 is inserted into a surgical site in thecollapsed configuration. The surgical site may be an opening (e.g.,natural orifice or incision) providing access to a body cavity of apatient. The dissector 10 may be inserted through a cannula or an accessport (not shown). When the distal ends 15, 17 are adjacent or in contactwith tissue to be dissected, the body 12 or tube 11 of the dissector 10are manipulated to dissect tissue with the distal ends 15, 17. In someinstances, the distal ends 15, 17 of the dissector 10 may not bluntlydissect tissue in contact therewith. In these instances, the dissector10 may be transitioned to the expanded configuration by extending thebody 12 from the tube 11 or retracting the tube 11 from over the arms14, 16.

When the dissector 10 transitions to the expanded configuration and thestring 18 is taut between the distal ends 15, 17 of the first and secondarms 14, 16, the string 18 may be used to dissect tissue. With thedissector 10 in the expanded configuration the tube 11 or the body 12may be laterally vibrated to dissect tissue with the string 18. It willbe appreciated that lateral vibration is oscillating movement of thestring 18 in a direction transverse to a longitudinal axis A-A of thebody 12 in a plane common with the distal ends 15, 17 as represented bythe arrows T in FIG. 1. Additionally or alternatively, the vibrationmechanism 20 may be configured to vibrate at least one of the first andsecond arms 14, 16 to vibrate the string 18.

With reference to FIGS. 4 and 5, another dissector 30 is provided inaccordance with the present disclosure including a body 32, a pivot pin33, a first arm 34, a second arm 36, and a string 38. The first arm 34is a rigid member that extends from the body 32 to a distal end 35 andthe second arm 36 is a rigid member that extends from the body 32 to adistal end 37 in substantially the same direction as the first arm 34.The distal ends 35, 37 may be substantially the same distance from thebody 32. The distal ends 35, 37 are blunt such that the distal ends 35,37 may atraumatically dissect tissue. One end of the string 38 iscoupled to the first arm 34 adjacent the distal end 35 and the other endof the string 38 is coupled to the second arm 36 adjacent the distal end37.

The pivot pin 33 is adjacent a distal end of the body 32. A proximal endof the first arm 34 and a proximal end of the second arm 36 are coupledto the body 32 by the pivot pin 33. The dissector 30 has an expandedconfiguration (FIG. 4) and a collapsed configuration (FIG. 5). In theexpanded configuration, the distal ends 35, 37 of the first and secondarms 34, 36, respectively, are spaced-apart and the string 38 is tautbetween the first and second arms 34, 36. In the collapsedconfiguration, the distal ends 35, 37 of the first and second arms 34,36, respectively, are close to one another such that the string 38 isslack between the first and second arms 34, 36. In the collapsedposition, the distal ends 35, 37 may be used for blunt dissection oftissue.

With additional reference to FIG. 7, the dissector 30 includes anactuation mechanism 40 configured to transition the dissector 30 betweenthe expanded configuration and the collapsed configuration. Theactuation mechanism 40 may include a biasing member 42 positioned aboutpivot pin 33 to bias the dissector 30 towards the expandedconfiguration. The biasing member 42 may be a torsion spring.

In some embodiments, the body 32 defines a lumen 41 and the pivot pin 33is disposed within a slot 44 defined in sidewalls of the body 32substantially parallel to a longitudinal axis A-A of the body 32. Inaddition, the actuation mechanism 40 includes a retractable member 46coupled to the pivot pin 33. The retractable member 46 configured totranslate the pivot pin 33 within the slot 44 along the longitudinalaxis of the body 32 to transition the dissector 30 between the expandedconfiguration, the collapsed configuration, and the transportconfiguration. The retractable member 46 may be disposed within thelumen 41 of the body 30. For example, when the pivot pin 33 ispositioned adjacent a distal end of the slot 44 the dissector 30 is inthe expanded configuration and when the pivot pin 33 is positionedadjacent a proximal end of the slot 44, the body 32 of the dissector 30engages the arms 34, 36 to collapse the dissector 30 to the collapsedconfiguration. When in the collapsed configuration, the distal ends 35,37 may protrude from the distal end of the body 32. In certainembodiments, the retractable member 44 may translate the pivot pin 33until the distal ends 35, 37 are drawn into the body 32 of the dissector30 such that the dissector 30 is in a transport configuration as shownin FIG. 6. The first and second arms 34, 36, being biased by the biasingmember 42, may bias the dissector 30 to the expanded configuration.Additionally or alternatively, the actuation mechanism 40 includes atube (not shown) substantially similar to the tube 11 of the dissector10 detailed above, as such the tube and the use thereof will not bedescribed in detail for reasons of brevity.

The dissector 30 may be used substantially similar to the dissector 10detailed above, as such the use of dissector 30 will not be detailed forreasons of brevity. In embodiments, the dissector 30 includes thevibration mechanism 20 configured to laterally vibrate the string 38.The vibration mechanism 20 may be operatively associated with one ormore of the body 32, the first arm 34, and the second arm 36.

With reference to FIGS. 8 and 9, yet another dissector 50 is provided inaccordance with the present disclosure and includes a body 52, a firstarm 54, a second arm 56, a string 58, a first jaw member 64, and asecond jaw member 66. The first jaw member 64 extends from the body 52to a distal end 65 and the second jaw member 66 extends from the body 52to a distal end 67. The distal ends 65, 67 are blunt to atraumaticallycontact and dissect tissue in contact therewith. The first and secondjaw members 64, 66 are coupled by a pivot pin or pivot 63 adjacent adistal end of the body 52. The first and second jaw members 64, 66 maybe moveable relative to one another between an open condition (FIG. 8)and a closed condition (FIG. 9). In the open condition, the distal ends65, 67 are spaced-apart a distance B as detailed below.

The first arm 54 is at least partially disposed within the first jawmember 64 and the second arm 56 is at least partially disposed withinthe second jaw member 66. It is also within the scope of this disclosurethat the first and second arms 54, 56 may be disposed on the outersurface of the first and second jaw members 64, 66 respectively.Proximal ends of each of the first and second arms 54, 56 extendproximally within the body 52. Alternatively, the proximal ends of eachof the first and second arms 54, 56 may be fixed within and relative toa respective one of the first and second jaw members 64, 66 adjacent thedistal end of the body 52. A distal end 55 of the first arm 54 isdisposed within the first jaw member 64 and a distal end 57 of thesecond arm 56 is disposed within the second jaw member 66. The distalends 55, 57 are substantially free to move transverse to a longitudinalaxis A-A of the body and may be substantially free to move along thelongitudinal axis A-A of a respective one of the jaw members 64, 66. Thedistal ends 55, 57 may be positioned about halfway along a length of arespective one of the first and second jaw members 64, 66 from the pivot63 to a respective one of the distal ends 65, 67. The first and secondarms 54, 56 are flexible such that each of the first and second arms 54,56 functions as a leaf spring with the proximal ends thereof fixed andthe distal ends 55, 57 thereof substantially free.

The surfaces of the first and second jaw members 64, 66 opposing oneanother each define an opening 68. The string 58 passes through theopenings 68 with one end of the string 58 coupled to the first arm 54adjacent the distal end 55 and the other end of the string 58 coupled tothe second arm 56 adjacent the distal end 57. When the first and secondjaw members 64, 66 are in the open condition as shown in FIG. 8, thefirst and second arms 54, 56 are in an expanded configuration such thatthe string 58 is taut and when the first and second jaw members 64, 66are in the closed condition as shown in FIG. 9, the first and secondarms 54, 56 are in a collapsed configuration such that the string 58 isslack.

With reference to FIGS. 10-12, exemplary embodiments of vibrationmechanisms 70, 80, 90 may be associated with the dissector 50 to induceoscillation (e.g., lateral, represented by arrows T, or longitudinal,represented by the arrows L, oscillation) of the string 58 when thestring 58 is taut. The jaw members 64, 66 are substantially isolatedfrom the vibration mechanism 70, 80, 90 such that the jaw members 64, 66remain substantially stationary during the oscillation of the string 58.

Referring now to FIG. 10, a vibration mechanism 70 includes a magneticcoil 72 and a magnet 74. The magnet 74 is coupled to the first arm 54adjacent the distal end 55. In embodiments, the magnet 74 is integrallyformed with the first arm 54. The magnetic coil 72 is disposed withinthe first jaw member 64 adjacent the magnet 74. The magnetic coil 72 isin communication with an energy source 73 that induces a magnetic fieldabout the magnetic coil 72. The magnetic field about the magnetic coil72 alternates to attract and repel the magnet 74 to induce oscillationof the string 58 (e.g., lateral oscillation). The energy source 73 maybe disposed within the dissector 50 or be external to the dissector 50.The vibration mechanism 70 may induce vibration in one of the first andsecond arms 54, 56 substantially similar to the resonant frequency ofthe one of the first and second arms 54, 56.

With reference to FIG. 11, a vibration mechanism 80 includes a rotaryelement 82 disposed on the first arm 54. The rotary element 82 may bepositioned adjacent the distal end 55 of the first arm 54. The rotaryelement 82 includes an eccentric mass 84 configured to rotate about acenter point 83 of the rotary element 82. The rotary element 82 may be arotary motor. The rotation of the eccentric mass 84 about the centerpoint 83 induces oscillation of the string 58. It will be appreciatedthat depending on the orientation of the rotary element 82, theoscillation of the string 58 may be lateral or longitudinal. Forexample, as shown in FIG. 11, the eccentric mass 84 rotatessubstantially parallel to the longitudinal axis of the first arm 54inducing lateral oscillation of the string 58 (i.e., oscillationtransverse to the longitudinal axis as represented by arrows T in FIG.11). Alternatively, the eccentric mass 84 may rotate orthogonal to thelongitudinal axis of the first arm 54 inducing longitudinal oscillationof the string 58 (i.e., oscillation along the longitudinal axis asrepresented by arrows L in FIG. 11). The vibration mechanism 80 mayinduce vibration in one of the first and second arms 54, 56substantially similar to the resonant frequency of the one of the firstand second arms 54, 56.

Referring to FIG. 12, a vibration mechanism 90 includes one or morepiezoelectric actuators 92, 94 associated with the first arm 54. Thepiezoelectric actuator 92 is a stripe actuator disposed on an outersurface of the first arm 54 such that when an electrical input isapplied to the actuator 92, the actuator 92 deflects the first arm 54 toinduce oscillation of the string 58. It will be appreciated thatdepending on the position of the actuator 92 along the first arm 54, theoscillation of the string 58 may be lateral or longitudinal. Forexample, as shown in FIG. 12, the actuator 92 is positioned along a topsurface of the first arm 54 to induce vibration in the first arm 54towards and away from second arm 56 to induce lateral oscillation of thestring 58 (i.e., oscillation transverse to the longitudinal axis asrepresented by arrows T in FIG. 12). Additionally or alternatively, theactuator 92 may be positioned along a side surface of the first arm 54(i.e., rotated 90°) to induce longitudinal oscillation of the string 58(i.e., oscillation along the longitudinal axis as represented by arrowsL in FIG. 12).

The piezoelectric actuator 94 is a stack actuator coupled to the firstarm 54 adjacent the distal end 55 such that when an electrical input isapplied to the actuator 94, the actuator 94 deflects the first arm 54 toinduce oscillation of the string 58. It will be appreciated thatdepending on the position of the actuator 94, the oscillation of thestring 58 may be lateral or longitudinal. For example, as shown in FIG.12, the actuator 94 is positioned substantially orthogonal to thelongitudinal axis of the first jaw member 64 to induce lateraloscillation of the string 58 (i.e., oscillation transverse to thelongitudinal axis as represented by arrows T in FIG. 12). Alternatively,the actuator 94 may be positioned substantially inline with thelongitudinal axis of the first jaw member 64 to induce longitudinaloscillation of the string 58 (i.e., oscillation along the longitudinalaxis as represented by arrows L in FIG. 12).

The vibration mechanism 90 may induce vibration in one of the first andsecond arms 54, 56 substantially similar to the resonant frequency ofthe one of the first and second arms 54, 56. It is within the scope ofthis disclosure that a vibration mechanism 90 may include an actuator 92and an actuator 94.

As shown, each of the vibration mechanisms 70, 80, 90 are disposedwithin the first jaw member to act directly on the first arm 54;however, it is within the scope of this disclosure that any of thevibration mechanisms 70, 80, 90 may also be disposed within the secondjaw member 66 to act directly on the second arm 56. In addition, it iscontemplated that one or more of the vibration mechanisms 70, 80, 90 maybe disposed within the first jaw member 64 or the second jaw member 66.The vibration mechanism vibrates the device in the sonic range (10-20KHz).

In use, the dissector 50 is inserted into a surgical site with the jawmembers 64, 66 in the closed condition. The distal ends 65, 67 of thejaw members 64, 66 may be used to dissect tissue. In some instances, thedistal ends 65, 67 may not bluntly dissect tissue in contact therewith.In these instances, the jaw members 64, 66 may be transitioned to theopen configuration. In the open configuration as shown in FIG. 8, thefirst and second jaw members 64, 66 are spaced apart a distance B. Thedistance B may allow target tissue (i.e., tissue to be dissected) topass between the first and second jaw members 64, 66 and preventnon-targeted tissue from passing between the first and second jawmembers 64, 66. For example, adhesions may be permitted to pass betweenthe first and second jaw members 64, 66 and bowels may be prevented frompassing between the first and second jaw members 64, 66.

When the first and second jaw members 64, 66 are in the open condition,the first and second jaw members 64, 66 are advanced to guide thetargeted tissue towards the string 58. It will be appreciated that whenthe first and second jaw members 64, 66 are in the open condition, thedissector 50 is in the expanded configuration such that the string 58 istaut. The string 58 is then oscillated either manually or with one ormore of the vibration mechanisms 70, 80, 90 detailed above to dissectthe targeted tissue.

Referring now to FIGS. 13-15, still yet another dissector 110 isprovided in accordance with the present disclosure and includes a body112, a peanut 114, and a retractable knife 118. The peanut 114 isattached to a peanut shaft 113 that extends from a distal end of thebody 112. The peanut 114 has a blunt distal end portion 115 foratraumatically dissecting tissue in contact therewith. The peanut 114may be made of an absorbent material such that the peanut 114 may absorbfluids that result from the dissection of tissue (e.g., blood). Thepeanut shaft 113 may be operatively associated with the vibrationmechanism 20 to induce lateral and/or longitudinal vibration of thepeanut 114. The vibration of the peanut 114 may assist in the dissectionof tissue in contact with the peanut 114.

The retractable knife 118 has a retracted position (FIG. 13), a firstexposed position (FIG. 14), and a second exposed position (FIG. 15). Inthe retracted position, the retractable knife 118 is disposed within thepeanut 114 such that the sharp edges of the retractable knife 118 areprevented from contacting tissue. In the first exposed position, theretractable knife 118 partially extends from the distal end portion 115of the peanut 114 such that leading edges 118 a of the retractable knifeare at least partially exposed to cut tissue in contact therewith. Inthe second exposed position, the retractable knife 118 extends from thedistal end portion 115 of the peanut 114. The leading edges 118 a of theretractable knife 118 are sharpened to cut tissue in contact therewith.The retractable knife 118 may be coupled to the distal end of a knifeshaft 117. The knife shaft 117 may extend from the proximal end of theretractable knife 118, through the peanut shaft 113, and into the body112. The knife 118 may vibrate with the peanut 114 when in the retractedposition or the exposed position.

In use, the dissector 110 is inserted into a surgical site with theretractable knife 118 in the retracted position. Similar to dissector 10described above, the dissector 110 may be inserted through an accessport (not shown). When the distal end portion 115 of the peanut 114 isadjacent or in contact with tissue to be dissected, the body 112 ismanipulated such that the distal end portion 115 atraumatically dissectstissue. When additional dissection is needed, the vibration mechanism 20may be activated to induce vibration in the peanut 114. The vibration ofthe peanut 114 may assist the distal end portion 115 in atraumaticallydissecting tissue. If the vibration of the peanut 114 still does notpermit the distal end portion 115 to dissect the tissue, the retractableknife blade 118 may be exposed from within the peanut 114 such that theleading edges 118 a sharply dissect the tissue. The retractable knifeblade 118 may then be returned to the retracted position such that thepeanut 114 may be used to bluntly dissect additional tissue.

While several embodiments of the disclosure have been shown in thedrawings, it is not intended that the disclosure be limited thereto, asit is intended that the disclosure be as broad in scope as the art willallow and that the specification be read likewise. Any combination ofthe above embodiments is also envisioned and is within the scope of theappended claims. Therefore, the above description should not beconstrued as limiting, but merely as exemplifications of particularembodiments. Those skilled in the art will envision other modificationswithin the scope and spirit of the claims appended hereto.

What is claimed:
 1. A method for dissecting tissue, the methodcomprising: inserting a dissector within a surgical site in a collapsedconfiguration thereof, the dissector including: a body; a first armextending from the body to a first distal end thereof; a second armextending from the body to a second distal end thereof; and a stringwith one end coupled to the first arm adjacent the first distal end andthe other end coupled to the second arm adjacent the second distal end;dissecting tissue with the first and second distal ends; expanding thefirst and second arms of the dissector from the collapsed configuration,wherein the string is slack, to an expanded configuration, wherein thestring is taut; and dissecting tissue with the string; whereindissecting tissue includes oscillating the string with a vibrationmechanism, and wherein the vibration mechanism is disposed on the firstarm.
 2. The method of claim 1, wherein dissecting tissue with the firstand second distal ends includes oscillating at least one of the firstand second arms with the vibration mechanism.
 3. The method of claim 1,wherein the vibration mechanism vibrates at a frequency of from tenHertz to twenty thousand Hertz.
 4. The method of claim 1 furthercomprising collapsing the first and second arms to the collapsedconfiguration after dissecting tissue.
 5. The method of claim 4 furthercomprising dissecting tissue with the first and second distal ends ofthe dissector after collapsing the first and second arms.
 6. The methodof claim 4, wherein collapsing the first and second arms includesretracting a pivot pin within a slot defined in the body to retractportions of the first and second arms into the body, the first andsecond arms coupled to the pivot pin.
 7. The method of claim 1, whereinexpanding the first and second arms includes retracting a tube from overa distal end of the body, the body disposed within a lumen of the tube.8. The method of claim 1, wherein expanding the first and second armsincludes extending the body from a distal end of a tube, the bodydisposed within a lumen of the tube.
 9. A method for dissecting tissue,the method comprising: inserting a dissector within a surgical site in acollapsed configuration thereof, the dissector including: a body; afirst arm extending from the body to a first distal end thereof; asecond arm extending from the body to a second distal end thereof; astring with one end coupled to the first arm adjacent the first distalend and the other end coupled to the second arm adjacent the seconddistal end; a first jaw member pivotally coupled to the body, the firstdistal end of the first arm disposed within the first jaw member; and asecond jaw member pivotally coupled to the body, the second distal endof the second arm disposed within the second jaw member; dissectingtissue with distal ends of the first and second jaw members; opening thefirst and second jaw members to expand the first and second arms of thedissector from the collapsed configuration, wherein the string is slack,to an expanded configuration, wherein the string is taut; and dissectingtissue with the string, wherein dissecting tissue with the stringincludes oscillating the string with a vibration mechanism, and whereinthe vibration mechanism is disposed within the first jaw member.
 10. Themethod of claim 9, wherein the vibration mechanism vibrates at afrequency of from ten Hertz to twenty thousand Hertz.
 11. The method ofclaim 9, wherein oscillating the string includes energizing thevibration mechanism, wherein the vibration mechanism comprises amagnetic coil disposed within the first jaw member adjacent a magnetdisposed on the first arm adjacent the first distal end.
 12. The methodof claim 9, wherein oscillating the string includes energizing thevibration mechanism, wherein the vibration mechanism comprises a rotaryelement disposed on the first arm adjacent the first distal end andwithin the first jaw member, the rotary element rotating an unbalancedmass to induce oscillation in the string.
 13. The method of claim 9,wherein oscillating the string includes energizing the vibrationmechanism, wherein the vibration mechanism comprises a piezoelectricactuator associated with the first arm.
 14. The method of claim 9further comprising closing the first and second jaw members to collapsethe first and second arms to the collapsed configuration afterdissecting tissue with the string.
 15. The method of claim 14 furthercomprising dissecting tissue with distal ends of the first and secondjaw members after closing the first and second jaw members.
 16. Themethod of claim 9, further comprising guiding tissue to be dissectedwith the string towards the string positioned between the first andsecond jaw members.